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I am waiting on my FF sensor, plug and fittings. Should be to me by Friday. I’ve got a handle on enabling the FF tune for my P59 PCM. I am N/A and looks like all I need to do is pin the plug to pin 56 for the ethanol content signal, pin 19 for the switched 12v and then a ground.
Do you have the E40 PCM? Or what do you have with your LS7?
You On that PCM you should be able to wire your sensor into C1 Pin 5 and then just enable your flex fuel tables in HPTuners or whatever tuning software you are using.
if you are high compression in high heat, from the (limited) info I currently know about E you should definitely see some gains. How substantial they are depends on many factors.
This is pulling the P59 ECU out from the V's mount location. Unpin the plastic underskirting from the plastic wheel well. I could not separate the underskirting from the front bumper but it flexes enough to get it out. There is a safety plate with a 10mm bolt in it covering the ECU which must be removed. Use a pair of needle nose pliers and a tiny eyeglass screwdriver to pop the grey plastic protective piece off the back as shown already done here. The writing you see is to keep myself straight while I have it apart. If you can remember everything, great for you but I can't lol.
This is pin 56 on the BLUE connector. You must pop the blue plastic cover piece off that inserts into the ECU, find pin 56 and use a small screwdriver or punch to push the round blue plastic plug in that slot back toward the where the wires are coming out. Not much force is needed. After that, you can insert your new wire (green in this picture) by just pushing it in. (NOTE: you will hear a click but the wire will not stop feeding through. Push it in till you hear the click then give it a little tug to make sure it's seated and visually inspect if it's even with the other ECU pins.) I had a few extra ECU pins I saved from my Monte SS swap from taking out A/C and a few other things the car didn't need. I'll post up a pic of what they look like later but you could easily go to a junk yard and get you a pig tail from a truck or something like that. THIS WILL BE THE FLEX FUEL SIGNAL WIRE.
Another shot of the ECU plug. You can see what blue plastic cover piece I am talking about here. You can also see the round blue plastic plugs on the opposite side of the ECU plug. I know this can get confusing but just read carefully.
Had to solder a couple wires together but I gave myself plenty to work with.
Routing the wire with the main harness going up into the engine bay from the driver's side
Little blurry but you can see the green wire peaking out and following the main harness.
Another routing pic
Routing along the injector harness.
Fuel rail and crossover feed line taken out of the car, I connected the FF sensor straight to the factory quick connect feed and attached the harness.
Power wire coming off the coil plug. 12v ignition (keyed on) Slot "H" on the plug wiring diagram below
Coil plug ground Slot "A" see diagram below. Also white signal wire from FF sensor mated with green pin 56 wire from ECU
originally was going to use the 16" hose I had lying around but it ended up being too long the way I have things set up. Luckily had a 12" line lying around as well. Black fittings are -6an to 3/8 quick disconnect from amazon and a -6an male to -6an female 90* from russel.
That's all I can show you tonight. I will get a parts list together eventually but I also got FIC 42lb @ 3bar injectors from another forum member so I don't run out of duty cycle (currently at 90%) and I need new injector o-rings but I can't get them till tomorrow
Here are the pinouts for the 429 Flex Fuel sensor and LS1/6 coil plug. I used A and H for power and ground but you can tap into anything you want with switched 12v power.
06-16-2019, 11:37 AM
Flex fuel add on 
